Lithium-ion (“Li-ion”) batteries are extensively used for energy storage applications. These applications include powering electric vehicles (“EVs”) and personal electric devices, such as laptops computers, digital music players, smart phones, and so forth. Li-ion batteries are particularly advantageous in these application due to their high energy density, high operational voltage, and low self-discharge rate. However, despite their widespread use and growing popularity, serious technical challenges remain in the use of Li-ion cells. These challenges include range per charge, charging time, cost, safety, and most importantly, cell lifetime. These challenges are especially pronounced in EV applications where long-term cycling and lifetimes of 10-15 years are expected.
Generally, it is difficult to provide in anode material that is capable of fast charging without also sacrificing the energy density of the material. Increasing the porosity of the material also decreases the tortuosity of the material, making it easier for lithium ions to traverse. However the material's porosity also directly impacts the volumetric energy density, as a more porous volume leads to less volume being occupied by active material.